For over a generation, researchers have utilized suspensions of monodisperse colloids as model systems to address questions concerning the assembly and structure of materials. Suspensions comprised of spherical colloids have long been the system of choice in large part because, until recently, the sphere was one of the few shapes that could be synthesized as monodisperse in large quantities. The recent vision that anisotropically shaped colloids may lead to an entirely new class of materials has caused a paradigm shift in the field. The advent of PRINT (Particle Replication In Non-wetting Templates) places the DeSimone group at the forefront of the colloidal assembly community with the unique ability to synthesize monodisperse colloids with unparalleled control over their shape, size and composition. Here, we highlight our recent results concerning the fabrication of a variety of PRINT particles and demonstrate their utility in directed self-assembly. Specifically, we have created magneto-responsive, non-spherical colloids via the incorporation of magnetite nanoparticles into the PRINT process. Adjusting processing conditions allows for the particle's magnetic conformation, with respect to its overall particle dimensions, to be tailored and the particles were manipulated while in suspension using an applied magnetic field. Additionally, we show a novel process to generate a range of monodisperse, amphiphilic diblock, triblock, and multiblock rods where the particle dimensions and their hydrophilic/hydrophobic ratio can be precisely tuned. Directed self-assembly of these anisotropic amphiphilic block particles at the water/oil interface gives new insights regarding the relationship between particle architecture and self-assembly behavior.

Shape specific colloidal particles

245th National Meeting (2013)

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